1. Field of the Invention
The present invention relates to a linear anatomic surgical stapling instrument and a surgical staple magazine used therein. More particularly, the invention relates to a transverse anatomic stapling instrument, which is also known as a transverse anastomosis instrument or device, for suturing body organs and tissue.
2. Description of the Prior Art
Historically, suturing of a surgical or other wound in organs and tissue has been done by hand. Conventional hand suturing techniques require a high degree of surgical skill. However, expertise in such techniques can vary widely from surgeon to surgeon, thereby resulting in widely varying quality in performance of the concluding steps of an operative procedure. In addition, even very skillful surgeons require a considerable amount of time to suture even relatively small wounds. Therefore, it is possible that an undesirable amount of blood may be lost during the. suturing operation.
Accordingly, there has been an increasing tendency in recent years to use surgical staples to suture body organs and tissue after a medical procedure. Surgical staples have been particularly effective in suturing body organs and tissue such as the lung, as well as the esophagus, the stomach, the duodenum, and other body organs in the intestinal tract.
The advent of surgical stapling has provided several marked advantages over known hand suturing techniques. First, since one or more rows of surgical staples are inserted into tissue using a specially adapted instrument that is relatively simple to operate, near uniformity of the closure from one surgeon to the next results. In addition, all staples in the closure are usually inserted simultaneously or in rapid sequence across the entire wound. Therefore, the closure is made very quickly to minimize loss of blood.
The specially adapted instruments for inserting surgical staples are mechanically operated and may be known as anastomosis devices, such as the transverse anastomosis devices of the type to which this invention relates. In such devices, the staples are loaded in one or more elongated rows into a magazine or cartridge. The magazine is then mounted in the device, which includes a mechanism for pushing, or driving, the staples from the magazine through two or more sections of tissue toward a deforming anvil. At the conclusion of the driving operation, the legs of each staple are clamped or bent, by engagement with the anvil, to a closed configuration to complete the suture and join the tissue sections together.
Known surgical stapling instruments of the type described above can be made of reusable materials. However, most stapling instruments employed today are made of disposable materials so that they can be discarded after use on a single patient. The cost of manufacture is thereby lowered and problems associated with handling, repairing, reconditioning, and sterilizing of previously used instruments are eliminated. Specifically, the risk of spreading infection from patient to patient due to improperly sterilized instruments is thus reduced and the surgeon can be confident that each fresh instrument he or she picks up is in good working order.
The conventional surgical anastomosis stapling instruments, of the type to which the present invention relates, more particularly include a handle having a trigger for firing the instrument and an elongated neck extending to a U-shaped distal end. A pair of jaws, one supporting an anvil and the other adapted to receive a disposable staple cartridge or magazine are mounted at the distal end to define the U-shape, which extends transversely to the neck. A clamp is provided to close the space between the anvil and the staple cartridge on the tissue layers to be sutured. Squeezing the trigger then drives the rows of staples, usually simultaneously, through the tissue layers and against the anvil where they are deformed to complete the suture.
While such known stapling instruments provide the advantage of surgical stapling mentioned above, they are nevertheless characterized by certain drawbacks. For example, these instruments are conventionally made of one-piece construction, with the distal end for receiving the staple cartridge extending from the handle. The design, however, can only be used with surgical staple magazines of one length. If a shorter or longer staple magazine is better suited for a particular suturing procedure, that is, to make a shorter or longer closure, a different size stapling instrument must be used. A second drawback of conventional one-piece stapling instruments is that the distal end resides in a fixed position with respect to the handle. Therefore, manipulation of the instrument to properly align the staple magazine and anvil carried in the distal end with the tissue to be sutured may be difficult because the entire stapling instrument must be maneuvered.
Still another drawback of known stapling instruments is that if the trigger is accidentally squeezed a staple cartridge will be wasted. More importantly, time will be wasted while the spent staple cartridge is replaced with a loaded cartridge and undesirable blood loss in the interim may result. While it is known to provide a safety latch on stapling instruments of the type described above to lock the trigger, the operator must remember to set the safety latch before and after the instrument is used for the latch to be effective.
Still, another difficulty with known stapling instruments is in obtaining proper alignment between and subsequent uniform clamping of the staple cartridge and the anvil together to clamp tissue therebetween. Proper alignment of the staple cartridge with the anvil is necessary to ensure the staples are properly deformed when driven toward the anvil, and uniform clamping of the tissue is desirable to properly position the tissue for suturing. In known instruments, however, the staple cartridge is pivoted about a supporting axis toward the anvil at one end of both to squeeze the tissue. However, this arrangement produces a non-uniform clamping force against the tissue because a greater force tends to be applied to the tissue closer to the pivot point.
Accordingly, further advantages and improvements in linear surgical stapling instruments are needed.